Microwave imaging of quasi-periodic pulsations at flare current sheet
Document Type
Article
Publication Date
12-1-2022
Abstract
Quasi-periodic pulsations (QPPs) are frequently detected in solar and stellar flares, but the underlying physical mechanisms are still to be ascertained. Here, we show microwave QPPs during a solar flare originating from quasi-periodic magnetic reconnection at the flare current sheet. They appear as two vertically detached but closely related sources with the brighter ones located at flare loops and the weaker ones along the stretched current sheet. Although the brightness temperatures of the two microwave sources differ greatly, they vary in phase with periods of about 10–20 s and 30–60 s. The gyrosynchrotron-dominated microwave spectra also present a quasi-periodic soft-hard-soft evolution. These results suggest that relevant high-energy electrons are accelerated by quasi-periodic reconnection, likely arising from the modulation of magnetic islands within the current sheet as validated by a 2.5-dimensional magnetohydrodynamic simulation.
Identifier
85143717281 (Scopus)
Publication Title
Nature Communications
External Full Text Location
https://doi.org/10.1038/s41467-022-35377-0
e-ISSN
20411723
PubMed ID
36509764
Issue
1
Volume
13
Grant
AST-2108853
Fund Ref
Alexander von Humboldt-Stiftung
Recommended Citation
Kou, Yuankun; Cheng, Xin; Wang, Yulei; Yu, Sijie; Chen, Bin; Kontar, Eduard P.; and Ding, Mingde, "Microwave imaging of quasi-periodic pulsations at flare current sheet" (2022). Faculty Publications. 2469.
https://digitalcommons.njit.edu/fac_pubs/2469
